American Olympic 100 metres hurdles gold medallist Brianna McNeal has been charged and provisionally suspended for violating World Athletics' Anti-Doping rules, the Athletics Integrity Unit (AIU) said on Thursday.
The AIU said McNeal, 29, who won gold at the 2016 Rio Olympics (then under her maiden name, Rollins) and was also world champion in 2013, was charged with "tampering within the results management process", but did not reveal any further details.
McNeal led a US clean sweep of the 100m hurdles at the 2016 Olympics but was banned for a year when she missed three out-of-competition drug tests, which constitutes an anti-doping rule violation.
The suspension, which was applied for the 2017 season, resulted in her missing the World Championships that year.
Having served a ban in the past, if McNeal is found guilty she could face an eight-year suspension - which would mean she would not be able to return to competition until she is almost 40. The allegation she is charged with carries a ban of up to four years.
McNeal's last major competition was in 2019, when she appeared at the World Championships but was disqualified in the first round after a false start.